Hemostasis valves are well-known, being currently used, for example, in arterial catheter introducers, used with catheters for performing percutaneous transluminal coronary angioplasty (PTCA), as well as catheters for angiographic procedures, for example where x-ray contrast fluid is inserted through a catheter into the coronary artery. The hemostasis valve is typically used to prevent the leakage of blood out of or around dilatation and other catheters which particularly enter into an artery, to prevent the reverse seepage of blood out of the patient into the operating field. Typically, hemostasis valves are conventionally positioned at the proximal ends of catheter introducers, which are used in conjunction with guidewires to facilitate the entrance of catheters into an artery or other blood vessel.
Numerous types of hemostasis valves are known. By way of example, see Stevens U.S. Pat. No. 4,000,739, Matsumoto et al. U.S. Pat. No. 4,610,655, Weinstein U.S. Pat. No. 4,626,245, and Hillstead U.S. Pat. No. 4,798,594.
In all of the previously cited patents, the hemostasis valves include an elastomeric partition of a solid, nonporous material which defines a slit through the partition, to facilitate the advancement of a catheter or guidewire through the hemostasis valve.
In the copending Kranys U.S. patent application No. 510,946, filed Apr. 19, 1990 and entitled Medical Instrument Valve Having Foam Partition Member, a hemostasis valve is disclosed for use with a catheter introducer or otherwise in which the elastomeric partition is a foamed elastomer. Such a material provides hemostasis, and may be used with a slit passing therethrough, or without a slit, since the foamed material is more easily penetrated by a guidewire or the like.
In the field of hemostasis valves such as those described above, it has been found to be desirable to place a hydrophilic lubricant material on the elastomeric partition of the hemostasis valve to facilitate the penetration of a catheter or guidewire therethrough. Particularly, hydratable hydrophilic materials are desirably used, such as the well-known hydrophilic lubricant sold under the brand name Hydromer. This material, and other hydrophilic lubricants, generally must be hydrated before they exhibit their desirable, slippery, lubricating characteristic. Typically, a separate hydration step is required by the addition of water to the lubricant, carried on the outer surface of the elastomeric partition member of hemostasis valves, followed often by a short waiting period, before the hydrophilic lubricant becomes sufficiently hydrated to exhibit its desirable lubricating characteristics.
Such hydrophilic lubricants tend to dry out after the hydration, so that the lubricity is again lost by the hemostasis valve, until another application of water is provided to rehydrate the material.
It would be desirable to provide a hemostasis valve which exhibits the good, slippery lubricity where the hydrophilic lubricant present remains hydrated for a long period of time, preferably during the entire procedure in which the hemostasis valve is involved, even if such a procedure might take hours or even days.
In accordance with this invention, a hemostasis valve is provided in which a hydratable lubricant material may be carried on the partition member, where the lubricant material can remain hydrated for an indefinitely long period of time during use, so that rehydration of the hydratable lubricant material ma not be required during use.